Segmented random access preamble processing method, apparatus, device and storage medium

Abstract

The application discloses a segmented random access preamble processing method and device, equipment and a storage medium. The method comprises the following steps: obtaining a first preamble baseband signal used for representing a random access preamble sequence; segmenting the first preamble baseband signal to obtain a second preamble baseband signal, wherein the second preamble baseband signal comprises a plurality of preamble subsequences, and an inter-segment guard interval is arranged between adjacent preamble subsequences; performing Doppler compensation on the second preamble baseband signal to obtain a third preamble baseband signal; and sending the third preamble baseband signal to a base station, so that the base station determines a timing advance based on the third preamble baseband signal. According to the scheme, the random access preamble is segmented and an inter-segment guard interval is arranged, the segmented preamble baseband signal is subjected to Doppler compensation, the detection deviation in a large Doppler scenario is reduced, and the timing advance estimation accuracy of the base station and the random access success rate are improved.

Description

Technical Field

[0001] This application relates to the field of wireless communication technology, and in particular to a segmented random access preamble processing method, apparatus, device and storage medium. Background Technology

[0002] In LEO (Low Earth Orbit) satellite communication systems, the satellite's speed relative to the ground terminal can reach approximately 7.5 km / s, resulting in a significant Doppler shift in the wireless link, which has a noticeable impact on random access preamble detection.

[0003] Current 5G NR (5G New Radio) random access mechanisms typically use the Zadoff-Chu (ZC) sequence as the preamble. While this sequence exhibits good autocorrelation characteristics under ideal conditions, it is highly sensitive to frequency offset. In LEO scenarios, a large Doppler frequency offset can disrupt the orthogonality of the ZC sequence, causing a decrease in correlation peaks or the generation of sidelobes, leading to missed detections or false alarms in preamble detection. Furthermore, the ambiguity function of the ZC sequence allows frequency offset to be converted into time-domain peak offset, making it difficult for the base station to distinguish whether the peak offset originates from propagation delay or Doppler frequency offset, thus affecting the accuracy of timing advance (TA) estimation. In addition, even if the terminal device uses an open-loop frequency offset compensation via a Synchronization Signal Block (SSB), significant residual frequency offset may still exist in the uplink due to crystal oscillator errors and uplink / downlink frequency differences, further reducing the reliability of random access preamble detection. Summary of the Invention

[0004] This application provides a segmented random access preamble processing method, apparatus, device, and storage medium. By segmenting the random access preamble baseband signal and setting inter-segment protection intervals between adjacent preamble sub-sequences, the impact of Doppler frequency offset on preamble detection is reduced, and the accuracy of timing advance calculation is improved.

[0005] In a first aspect, this application provides a segmented random access preamble processing method, applied to a terminal device, comprising: Acquire the first preamble baseband signal used to represent the random access preamble sequence; The first preamble baseband signal is segmented to obtain a second preamble baseband signal. The second preamble baseband signal includes multiple preamble sub-sequences, and an inter-segment guard interval is set between adjacent preamble sub-sequences. Doppler compensation is performed on the second preamble baseband signal to obtain a third preamble baseband signal, which is then sent to the base station for the base station to determine timing advance based on the third preamble baseband signal.

[0006] Secondly, this application provides a segmented random access preamble processing device, applied to a terminal device, comprising: The signal acquisition module is configured to acquire a first preamble baseband signal representing a random access preamble sequence; The signal segmentation module is configured to segment the first preamble baseband signal to obtain a second preamble baseband signal. The second preamble baseband signal includes multiple preamble sub-sequences, and an inter-segment guard interval is set between adjacent preamble sub-sequences. The compensation transmission module is configured to perform Doppler compensation on the second preamble baseband signal to obtain a third preamble baseband signal, and transmit the third preamble baseband signal to the base station for the base station to determine the timing advance based on the third preamble baseband signal.

[0007] Thirdly, this application provides a segmented random access preamble processing device, comprising: One or more processors; A memory that stores one or more programs, which, when executed by one or more processors, cause the one or more processors to implement the segmented random access preamble processing method as described in the first aspect.

[0008] Fourthly, this application provides a storage medium containing computer-executable instructions, which, when executed by a computer processor, are used to perform the segmented random access preamble processing method as described in the first aspect.

[0009] In this application, a segmented random access preamble processing method based on preamble segmentation construction and terminal equipment Doppler precompensation mechanism is constructed, achieving stable transmission and reliable detection support for uplink random access preambles. This method acquires a first preamble baseband signal representing the random access preamble sequence, segments the first preamble baseband signal to obtain a second preamble baseband signal comprising multiple preamble sub-sequences, and sets inter-segment guard intervals between adjacent preamble sub-sequences to form a clear segmented structure. Doppler compensation is applied to the second preamble baseband signal to obtain a third preamble baseband signal, which is then transmitted to the base station, enabling the base station to determine timing advance based on this signal. This scheme can reduce the impact of Doppler frequency offset on random access preamble detection and improve the accuracy of timing advance estimation, making it suitable for low-Earth orbit satellite communication, non-terrestrial network communication, and long-distance uplink random access scenarios. Attached Figure Description

[0010] Figure 1 This is a flowchart of a segmented random access preamble processing method provided in an embodiment of this application; Figure 2 This is a flowchart of a method for generating a third preamble baseband signal provided in an embodiment of this application; Figure 3 This is a flowchart of a timing advance determination method provided in an embodiment of this application; Figure 4 This is a flowchart of a method for determining the phase difference of a subsequence provided in an embodiment of this application; Figure 5 This is a flowchart of a timing advance calculation method provided in an embodiment of this application; Figure 6 This is a flowchart illustrating the steps of a segmented random access preamble processing method provided in an embodiment of this application. Figure 7 This is a structural block diagram of a segmented random access preamble processing device provided in an embodiment of this application; Figure 8 This is a schematic diagram of the structure of a segmented random access preamble processing device provided in an embodiment of this application. Detailed Implementation

[0011] To make the objectives, technical solutions, and advantages of this application clearer, specific embodiments of this application will be described in further detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are merely for explaining this application and not for limiting it. It should also be noted that, for ease of description, only the parts relevant to this application are shown in the drawings, not all of them. Before discussing exemplary embodiments in more detail, it should be mentioned that some exemplary embodiments are described as processes or methods depicted as flowcharts. Although the flowcharts describe operations (or steps) as being processed sequentially, many of these operations can be performed in parallel, concurrently, or simultaneously. Furthermore, the order of the operations can be rearranged. A process can be terminated when its operation is completed, but it may also have additional steps not included in the drawings. A process can correspond to a method, function, procedure, subroutine, subroutine, etc.

[0012] The terms "first," "second," etc., used in the specification and claims of this application are used to distinguish similar objects and not to describe a specific order or sequence. It should be understood that such use of data can be interchanged where appropriate so that embodiments of this application can be implemented in orders other than those illustrated or described herein, and the objects distinguished by "first," "second," etc., are generally of the same class and the number of objects is not limited; for example, a first object can be one or more. Furthermore, in the specification and claims, "and / or" indicates at least one of the connected objects, and the character " / " generally indicates that the preceding and following objects are in an "or" relationship.

[0013] Currently, with the development of space-ground converged communication, satellite internet, and 5G / 6G non-terrestrial networks, the reliability of random access in LEO satellite communication scenarios has become a critical issue. Because LEO satellites can move at speeds of up to approximately 7.5 km / s relative to the ground, the uplink is prone to significant Doppler shift, posing a significant challenge to traditional 5G NR preamble detection mechanisms.

[0014] Current 5G NR random access preambles typically employ ZC sequences, which exhibit good autocorrelation characteristics in conventional terrestrial communication scenarios but are highly sensitive to frequency offset. In LEO satellite communication, large frequency offsets disrupt the orthogonality and correlation peak characteristics of ZC sequences, leading to a decrease in correlation peak value and enhanced sidelobes, which in turn causes problems such as missed preamble detection and false peak detection. Furthermore, ZC sequences also exhibit time-frequency ambiguity under frequency offset conditions; the frequency offset may manifest as a shift in the time domain position of the correlation peak, making it difficult for the base station to distinguish whether the shift is caused by propagation delay or Doppler frequency shift, resulting in incorrect timing advance estimation. Even with open-loop pre-compensation based on the downlink synchronization signal, the uplink may still have a significant residual frequency offset due to crystal oscillator errors, uplink-downlink frequency differences, and dynamic changes in the link. Therefore, existing random access preamble processing methods are insufficient to meet the requirements of high-reliability access and accurate timing estimation in LEO satellite communication.

[0015] Therefore, this invention aims to propose a segmented random access preamble processing method, which can improve the stability of random access preamble transmission and the accuracy of timing advance estimation in LEO satellite communication and large frequency offset scenarios. This method is applied to a terminal device, which acquires the first preamble baseband signal and segments it to obtain a second preamble baseband signal comprising multiple preamble sub-sequences, setting inter-segment guard intervals between adjacent preamble sub-sequences. The terminal device performs Doppler compensation on the second preamble baseband signal to obtain a third preamble baseband signal, which is then sent to the base station, enabling the base station to determine the timing advance based on the third preamble baseband signal. This method can reduce the impact of Doppler frequency shift on preamble detection, improve random access reliability, and is suitable for satellite internet, non-terrestrial networks, and long-distance uplink random access scenarios.

[0016] Figure 1 This is a flowchart of a segmented random access preamble processing method provided in an embodiment of this application. (Reference) Figure 1 The segmented random access preamble processing method specifically includes: S110. Obtain the first preamble baseband signal used to represent the random access preamble sequence.

[0017] The random access preamble sequence can be a known sequence sent by the terminal device during the random access process, and the first preamble baseband signal can be a baseband signal formed after the random access preamble sequence has undergone baseband modulation processing, which is used as the basis signal for the generation of subsequent signals.

[0018] In one embodiment, the method for obtaining the first preamble baseband signal may be: reading the preamble sequence corresponding to the target random access resource from a preset preamble sequence library, converting the read preamble sequence into a discrete baseband sampling sequence according to a preset sampling period, and determining the discrete baseband sampling sequence as the first preamble baseband signal.

[0019] Through the above steps, the first preamble baseband signal used to represent the random access preamble sequence can be obtained, providing basic signal data for subsequent preamble expansion, subsequence division, phase compensation, correlation detection, and random access synchronization processing.

[0020] S120. The first preamble baseband signal is segmented to obtain a second preamble baseband signal. The second preamble baseband signal includes multiple preamble sub-sequences, and an inter-segment guard interval is set between adjacent preamble sub-sequences.

[0021] The second preamble baseband signal can be a preamble baseband signal reorganized from multiple preamble sub-sequences and inter-segment guard intervals; the inter-segment guard interval can be an idle sampling interval, a zero-fill interval, or a low-power guard interval set between adjacent preamble sub-sequences to reduce interference between adjacent preamble sub-sequences and to provide a clear inter-segment time reference for subsequent phase difference estimation and residual Doppler frequency shift calculation.

[0022] In one embodiment, segmenting the first preamble baseband signal can be achieved by: obtaining a preset subsequence length of the preamble subsequence; dividing the first preamble baseband signal into multiple consecutive truncation intervals according to the sequence length; and determining the baseband sampling data within each truncation interval as multiple preamble subsequences; obtaining a preset inter-segment time interval, which can be preset to 10μs, 16μs, 20μs, or 32μs; and inserting a number of guard sampling points corresponding to the inter-segment time interval between two adjacent preamble subsequences to obtain a second preamble baseband signal comprising multiple preamble subsequences and multiple inter-segment guard intervals. The guard sampling points can be zero-value sampling points or low-amplitude sampling points that satisfy a preset power constraint. The structure of the resulting second preamble baseband signal is shown below:

[0023] in, This is the second preamble baseband signal. For cyclic prefix, For the first A sequence of preamble codes, For inter-section protection intervals, This is the tail guard time. The cyclic prefix is ​​a guard interval added before each symbol in an orthogonal frequency division multiplexing system. It forms a cyclic structure by copying the tail signal of the symbol to the head. It is mainly used to eliminate inter-symbol interference and inter-carrier interference caused by multipath propagation. The tail guard time is an additional guard interval reserved after the end of the effective part of the preamble. It is used to prevent the tail multipath delay of the signal segment from affecting subsequent signal segments.

[0024] Through the above steps, the first preamble baseband signal can be divided into multiple preamble sub-sequences, and inter-segment guard intervals can be set between adjacent preamble sub-sequences, so that the second preamble baseband signal has a clear segmented structure and inter-segment time reference, providing a signal structure basis for subsequent sub-sequence correlation calculation, sub-sequence phase difference extraction, residual Doppler frequency shift estimation, and timing advance determination.

[0025] S130. Perform Doppler compensation on the second preamble baseband signal to obtain a third preamble baseband signal, and send the third preamble baseband signal to the base station for the base station to determine the timing advance based on the third preamble baseband signal.

[0026] The third preamble baseband signal can be a random access preamble baseband signal used for actual transmission after Doppler compensation, and the base station can be a satellite base station.

[0027] Through the above steps, Doppler pre-compensation can be performed on the segmented preamble baseband signal before sending the random access preamble, reducing the frequency offset caused by the relative motion between the terminal equipment and the base station, so that the receiver can obtain a third preamble baseband signal with more stable phase change, thereby improving the accuracy of preamble detection, residual Doppler estimation and timing advance determination.

[0028] Optionally, Figure 2 This is a flowchart illustrating a method for generating a third preamble baseband signal according to an embodiment of this application. (Reference) Figure 2 The method for generating the third preamble baseband signal specifically includes: S1301. Obtain the synchronization information block signal, and determine the Doppler frequency offset and Doppler rate of change based on the synchronization information block signal.

[0029] Among them, the synchronization information block signal can be the downlink synchronization and system information signal periodically broadcast by the base station; the Doppler frequency offset can be the carrier frequency offset caused by the relative motion between the terminal device and the base station when the terminal device receives the synchronization information block signal; the Doppler change rate can be the rate at which the Doppler frequency offset changes with time, used to characterize the dynamic change trend of the Doppler frequency shift during the random access preamble transmission.

[0030] In one embodiment, the synchronization information block signal can be obtained by the terminal device receiving the synchronization information block broadcast by the base station during the downlink synchronization search process, and performing downconversion, filtering, analog-to-digital conversion and baseband demodulation on the received downlink radio frequency signal to obtain the synchronization information block signal.

[0031] In one embodiment, the method for determining the Doppler frequency offset based on the synchronization information block signal may be: the terminal device performs frequency offset estimation on the synchronization sequence in the synchronization information block signal, calculates the frequency offset of the received synchronization information block signal relative to the local reference frequency, and determines the frequency offset as the Doppler frequency offset.

[0032] In one embodiment, the method for determining the Doppler rate of change based on the synchronization information block signal can be as follows: the terminal device estimates the Doppler frequency offset in multiple consecutive synchronization information block periods, obtains multiple Doppler frequency offset values ​​corresponding to different reception times, and calculates the Doppler rate of change based on the frequency offset values ​​and time intervals between adjacent reception times. The specific calculation formula is as follows:

[0033] in, For Doppler change rate, For the first Doppler frequency offset corresponding to each synchronization information block For the first Doppler frequency offset corresponding to each synchronization information block This is the time interval for receiving two synchronization information blocks.

[0034] Through the above steps, the Doppler frequency offset and Doppler change rate before the random access preamble is transmitted can be obtained using the synchronization information block signal. This provides a frequency correction basis for subsequent Doppler compensation of the second preamble baseband signal, generation of the third preamble baseband signal, and improvement of the preamble detection accuracy on the base station side.

[0035] S1302. Calculate the uplink pre-compensation amount based on the Doppler frequency offset and the Doppler rate of change, and generate a rotation factor based on the uplink pre-compensation amount.

[0036] The uplink pre-compensation amount can be a frequency pre-correction parameter applied by the terminal device before transmitting the third preamble baseband signal, and the rotation factor can be a complex exponential factor generated based on the uplink pre-compensation amount, used to perform sample-by-sample phase rotation compensation on the second preamble baseband signal.

[0037] In one embodiment, the uplink pre-compensation amount can be calculated as follows: obtain the downlink carrier frequency corresponding to the synchronization information block signal and the uplink carrier frequency corresponding to the random access preamble; calculate the ratio between the downlink carrier frequency and the uplink carrier frequency; convert the downlink measured Doppler frequency offset into the uplink frequency band corresponding to the Doppler frequency offset; and invert the converted uplink Doppler frequency offset to obtain the uplink pre-compensation amount. The specific calculation formula is as follows:

[0038] in, This is the uplink pre-compensation amount. The Doppler frequency offset measured in the downlink direction. For uplink carrier frequency, The downlink carrier frequency is indicated by the negative sign, which signifies that the terminal device applies a frequency correction in the opposite direction to the uplink Doppler frequency offset.

[0039] In one embodiment, the rotation factor can be generated based on the uplink pre-compensation amount as follows: Since it is necessary to consider the phase nonlinearity change caused by the Doppler rate of change during the preamble duration, a time-varying rotation factor can be generated based on the uplink pre-compensation amount and the uplink Doppler rate of change. The specific calculation formula is as follows:

[0040] in, For the first Rotation factor corresponding to each sampling point The upward Doppler rate of change. For the first The sampling time corresponding to each sampling point This is the uplink pre-compensation amount.

[0041] Through the above steps, the pre-compensation amount suitable for uplink random access preamble transmission can be calculated based on the Doppler frequency offset and Doppler change rate estimated from the synchronization information block signal, and a rotation factor corresponding to the sampling time can be generated, so that the second preamble baseband signal can complete frequency and phase pre-correction before transmission, thereby reducing the uplink Doppler residual caused by high-speed satellite movement or link frequency band differences, and improving the accuracy of preamble correlation detection and timing advance estimation on the base station side.

[0042] S1303. The second preamble baseband signal is compensated based on the rotation factor to obtain the third preamble baseband signal.

[0043] The third preamble baseband signal can be the preamble baseband signal used for transmission after completing the uplink Doppler pre-correction.

[0044] In one embodiment, the method for compensating the second preamble baseband signal based on the rotation factor can be as follows: obtain the complex sample values ​​of each sampling point in the second preamble baseband signal, multiply each complex sample value by the corresponding rotation factor to obtain the sample value after phase precorrection, and combine multiple sample values ​​after phase precorrection according to the original sampling order to form the third preamble baseband signal.

[0045] Through the above steps, the rotation factor can be used to perform sample-by-sample phase pre-compensation on the second preamble baseband signal, so that the predicted uplink Doppler frequency offset and the influence of Doppler dynamic changes can be canceled before the third preamble baseband signal is transmitted. This reduces the residual frequency offset when the base station receives the preamble, and improves the concentration of preamble correlation peaks, the stability of subsequence phase difference estimation, and the accuracy of timing advance determination.

[0046] Optionally, Figure 3 This is a flowchart illustrating a method for determining timing advance provided in an embodiment of this application. (Reference) Figure 3 The method for determining the timing advance specifically includes: S1304. Extract multiple preamble sequence numbers from the third preamble baseband signal.

[0047] The third preamble baseband signal can be a baseband preamble signal sent by the terminal device, and the preamble sub-sequence can be a preamble segment formed by combining according to a preset coding rule. Each preamble sub-sequence can be used to carry information related to synchronization identification, terminal device differentiation, channel estimation, or access detection.

[0048] In one embodiment, the method of receiving the third preamble baseband signal may be: receiving the radio frequency preamble signal sent by the terminal device through the base station receiving link, and performing down-conversion, filtering, analog-to-digital conversion and baseband demodulation processing on the radio frequency preamble signal to obtain the third preamble baseband signal.

[0049] In one embodiment, the method for extracting multiple preamble sub-sequences from the third preamble baseband signal can be as follows: the third preamble baseband signal is segmented according to a preset preamble length, and the resulting multiple signal segments are determined as preamble sub-sequences. The time length corresponding to the preamble can be 64μs. With a sampling rate of 30.72MHz, 64μs corresponds to approximately 1966 sampling points. Therefore, the third preamble baseband signal can be truncated every 1966 sampling points to obtain multiple third preamble sub-sequences of the same length.

[0050] Through the above steps, multiple preamble sub-sequences can be separated from the third preamble baseband signal sent by the terminal device, providing basic data for subsequent preamble identification, synchronization parameter estimation, terminal device access determination, and channel state analysis.

[0051] S1305. Calculate the subsequence phase difference between adjacent preamble subsequences.

[0052] Among them, adjacent preamble code sequences can be two preamble code sequences that are continuously distributed in the order of arrangement, and the phase difference of the subsequences can be used to characterize the phase shift between two adjacent preamble code sequences.

[0053] In one embodiment, the correlation result can be determined by: obtaining the first preamble sequence and the second preamble sequence adjacent to it, performing conjugate multiplication on the corresponding sampling points in the two preamble sequences, and accumulating the conjugate multiplication results to obtain the correlation result between the adjacent preamble sequences.

[0054] In one embodiment, the subsequence phase difference can be determined by: performing phase extraction on the correlation results to obtain the phase angle corresponding to the correlation results, and determining the phase angle as the subsequence phase difference between adjacent preamble subsequences.

[0055] Through the above steps, phase offset information can be extracted based on the correlation characteristics between adjacent preamble code sequences, providing phase reference data for subsequent frequency offset estimation, synchronization correction, and signal demodulation of terminal equipment.

[0056] Optionally, Figure 4 This is a flowchart illustrating a method for determining the phase difference of a subsequence according to an embodiment of this application. (Reference) Figure 4 The method for determining the phase difference of the subsequence specifically includes: S13051. Determine multiple candidate time offset positions based on the preset time offset search window and the preset sampling period.

[0057] The time offset search window can be a time interval used to limit the timing detection range of the preamble. The sampling period can be the time interval between adjacent sampling points when the base station performs discrete sampling on the third preamble baseband signal. The time offset candidate positions can be multiple positions to be detected obtained by discretely dividing the time offset search window according to the sampling period. Each time offset candidate position can correspond to a possible preamble start position. For example, the time offset search window can be set to [-10μs, 10μs], and the sampling period can be set to 32.55ns. Then, starting from -10μs, a time offset candidate position can be determined every 32.55ns until 10μs, thus obtaining approximately 615 time offset candidate positions.

[0058] In one embodiment, the method for determining multiple time offset candidate positions may be as follows: taking the start time of the time offset search window as the initial candidate position, and sequentially increasing the time offset search window according to a preset sampling period to obtain multiple discrete time positions, and determining each discrete time position as a time offset candidate position.

[0059] Through the above steps, multiple discrete time offset candidate positions can be constructed within the preset time offset search window, providing a timing detection basis for subsequent preamble correlation operations, sub-correlation value calculations, and correlation peak searches at different candidate positions.

[0060] S13052. At the multiple time offset candidate positions, perform correlation calculations on each of the preamble sub-sequences to obtain the sub-correlation values ​​corresponding to each preamble sub-sequence at each of the multiple time offset candidate positions.

[0061] The subcorrelation value can be a complex correlation result obtained by performing correlation operations between the preamble subsequence and the local reference subsequence at a certain time offset candidate position. The subcorrelation value can be used to characterize the degree of matching between the time offset candidate position and the corresponding preamble subsequence.

[0062] In one embodiment, the correlation calculation for each preamble subsequence can be performed as follows: for any candidate time offset position, the received sampled data that matches the length of each preamble subsequence is extracted from its corresponding sampling interval, and the extracted received sampled data is multiplied by the corresponding local reference subsequence using conjugate multiplication. The results of the conjugate multiplication are then accumulated to obtain the subcorrelation value of the preamble subsequence at the current candidate time offset position.

[0063] Through the above steps, the relevant detection results corresponding to each preamble code sequence can be obtained at multiple time offset candidate positions, thereby forming the basic relevant data for subsequent phase difference determination, phase compensation, correlation value merging and timing advance determination.

[0064] S13053. At the same time offset candidate position, calculate the conjugate product of the subcorrelation values ​​of adjacent preamble subsequences.

[0065] The subcorrelation value of adjacent preamble subsequences can be the complex correlation result obtained by performing correlation calculations between two adjacent preamble subsequences and their corresponding local reference subsequences at the same time offset candidate position.

[0066] In one embodiment, the conjugate product can be calculated by: obtaining the first... Subcorrelation values ​​of each preamble subsequence at the current candidate time offset position and the Subcorrelation values ​​of preamble subsequences at the same time offset candidate position ,right Conjugation process is performed to obtain ,Will and Multiplying them yields the conjugate product of adjacent preamble codeword sequences. The specific calculation formula is shown below:

[0067] in, It is the conjugate product of adjacent preamble codeword sequences. For the first Subcorrelation values ​​of a preamble subsequence, For the first The conjugate value of the subcorrelation values ​​of the preamble subsequences.

[0068] Through the above steps, the complex subcorrelation values ​​of adjacent preamble subsequences can be used to construct the basis for phase difference calculation at the same time offset candidate position, so that the phase difference of the subsequence can be determined according to the phase angle of the conjugate product, providing a basis for residual Doppler frequency shift estimation and phase compensation.

[0069] S13054. Determine the subsequence phase difference corresponding to the candidate time offset position based on the conjugate product.

[0070] The subsequence phase difference can be used to characterize the phase rotation relationship between adjacent preamble subsequences.

[0071] In one embodiment, the phase difference of the subsequences can be calculated by: applying the conjugate product Perform phase extraction and calculation phase angle The phase angle is determined as the first The nth preamble sequence and the nth The phase difference between the preamble subsequences. The specific formula for calculating the phase angle is as follows:

[0072] in, It is a two-parameter arctangent function. for The imaginary part, for The real part.

[0073] Through the above steps, phase rotation information can be directly extracted from the complex subcorrelation values ​​of adjacent preamble subsequences, avoiding reliance on the original sampling points for phase estimation alone. This improves the stability and noise resistance of subsequence phase difference calculation and provides a basis for phase correction for subsequent phase compensation, coherent merging, and timing advance determination of subcorrelation values.

[0074] Optionally, determining the subsequence phase difference corresponding to the candidate time offset position based on the conjugate product includes: Calculate the phase angle of the conjugate product to obtain the initial phase difference between adjacent preamble codeword sequences.

[0075] The phase angle can be the angle of the conjugate product in the complex plane, and the initial phase difference can be used to represent the phase offset between adjacent preamble code sequences that has not been smoothed, filtered, or corrected.

[0076] In one embodiment, the initial phase difference can be calculated by: obtaining the conjugate product corresponding to adjacent preamble code sequences, extracting the real and imaginary parts of the conjugate product, and calculating the arctangent of the real and imaginary parts of the conjugate product to obtain the initial phase difference.

[0077] Through the above steps, the complex correlation between adjacent preamble subsequences can be converted into phase offset information, providing basic phase data for subsequent phase difference filtering, phase unwrapping, residual Doppler shift estimation, and subcorrelation value phase compensation.

[0078] Phase unwrapping is performed on the initial phase difference to obtain the unwrapped phase difference of adjacent preamble codeword sequences.

[0079] Among them, the unwrapping phase difference can be eliminated The continuous phase difference obtained after the periodic jump effect is used to more accurately characterize the true phase rotation between adjacent preamble codeword sequences.

[0080] In one embodiment, the method for unwrapping the initial phase difference can be as follows: multiple initial phase differences are obtained according to the order of the preamble code sequence, and the phase change between adjacent initial phase differences is calculated sequentially; if the phase change is greater than a preset positive transition threshold, the subsequent initial phase difference is subtracted. If the phase change is less than the preset negative transition threshold, then the subsequent initial phase difference is added. This allows us to obtain a continuously changing untangled phase difference.

[0081] By following the steps described above, the limitation of the initial phase difference by the principal value range of the arctangent can be eliminated. Periodic jumps make the phase difference between adjacent preamble code sequences more continuous and stable, providing a reliable phase basis for subsequent calculation of residual Doppler frequency shift, generation of phase compensation factor, and improvement of timing advance estimation accuracy.

[0082] The average value of the unwrapped phase difference is calculated to obtain the subsequence phase difference corresponding to the candidate time offset position.

[0083] The phase difference of the subsequence can be used as the unified phase difference estimation result corresponding to the candidate position of the time offset.

[0084] In one embodiment, the subsequence phase difference can be calculated by: obtaining the unwrapped phase difference corresponding to multiple adjacent preamble subsequences at the same time offset candidate position, summing the multiple unwrapped phase differences, and dividing the summation result by the number of unwrapped phase differences to obtain the subsequence phase difference corresponding to the time offset candidate position.

[0085] Through the above steps, the unwrapped phase differences corresponding to multiple adjacent preamble subsequences can be fused into a unified subsequence phase difference, making the phase difference estimation results smoother and more stable, and providing reliable phase parameters for subsequent calculation of residual Doppler frequency shift, execution of phase compensation, and determination of timing advance.

[0086] S1306. Based on the phase difference of the sub-sequences, the sub-correlation values ​​of the multiple preamble sub-sequences are compensated and merged to obtain the timing advance.

[0087] Among them, the subcorrelation value can be the correlation detection result obtained after performing correlation operations between each preamble subsequence and the local reference preamble sequence, and the timing advance can be used to characterize the time offset that the terminal device needs to adjust in advance relative to the reference reception time.

[0088] In one embodiment, the method for compensating the subcorrelation values ​​of multiple preamble subsequences can be as follows: convert the phase difference of the subsequences into a complex exponential form to obtain the phase rotation factor between adjacent preamble subsequences, and multiply the subcorrelation values ​​of multiple preamble subsequences by the corresponding phase rotation factor to achieve compensation and correction of the subcorrelation values ​​of multiple preamble subsequences.

[0089] In one embodiment, the method for merging multiple sub-correlation values ​​after compensation can be: coherently accumulating the multiple sub-correlation values ​​that have completed phase correction according to the order of the sub-sequences to obtain the merged correlation value.

[0090] In one embodiment, the timing advance can be determined by: determining the sampling position corresponding to the relevant peak value in the merged relevant values, calculating the sampling offset between the sampling position and the preset timing reference position, multiplying the sampling offset by the sampling period to obtain the time offset, and determining the calculated time offset as the timing advance.

[0091] Through the above steps, phase compensation and coherent merging of the correlation detection results of multiple preamble sub-sequences can be performed using the sub-sequence phase difference, thereby improving the detection accuracy of correlation peaks and noise resistance, and thus more accurately determining the timing advance corresponding to the terminal equipment, providing a basis for subsequent uplink synchronization adjustment and signal receiving window configuration.

[0092] Optionally, Figure 5 This is a flowchart illustrating a timing advance calculation method provided in an embodiment of this application. (Reference) Figure 5 The specific method for calculating the timing advance includes: S13061. Obtain the subsequence duration of the preamble subsequence and the protection interval duration of the inter-segment protection interval, and add the subsequence duration and the protection interval duration to obtain the inter-segment time interval.

[0093] The subsequence duration can be the duration of a single preamble subsequence in the time domain, the guard interval duration can be the reserved time between two adjacent preamble subsequences, and the inter-segment time interval can be the time interval between the phase reference points of adjacent preamble subsequences, which is used to calculate the residual Doppler frequency shift based on the phase difference.

[0094] In one embodiment, the subsequence duration can be obtained by: obtaining the number of sampling points corresponding to the preamble subsequence and the preset sampling period, multiplying the number of sampling points by the preset sampling period to obtain the subsequence duration of the preamble subsequence.

[0095] In one embodiment, the protection interval duration can be obtained by: obtaining the number of protection sampling points corresponding to the inter-segment protection interval, and multiplying the number of protection sampling points by a preset sampling period to obtain the protection interval duration.

[0096] In one embodiment, the inter-segment time interval can be calculated by adding the subsequence duration to the guard interval duration to obtain the inter-segment time interval between adjacent preamble subsequences. Through the above steps, the inter-segment time interval between adjacent preamble sub-sequences can be determined based on the duration of the preamble sub-sequence and the duration of the inter-segment guard interval, providing a time reference for subsequent calculation of residual Doppler frequency shift by combining sub-sequence phase differences, generation of phase compensation factors, and execution of correlation value compensation merging.

[0097] S13062. Calculate the residual Doppler frequency shift based on the inter-segment time interval and the phase difference of the sub-sequence.

[0098] The inter-segment time interval can be the time difference between phase reference points of adjacent sub-sequences, including the sub-sequence length and guard interval; the residual Doppler frequency shift can be the Doppler frequency shift that still exists after the initial frequency offset compensation, used to characterize the residual frequency deviation caused by the relative motion between the terminal equipment and the base station.

[0099] In one embodiment, the residual Doppler frequency shift can be calculated based on the inter-segment time interval and the sub-sequence phase difference by dividing the sub-sequence phase difference by the inter-segment time interval to obtain the phase rotation rate per unit time, and then dividing the phase rotation rate by... The residual Doppler frequency shift is obtained. The specific calculation formula is shown below:

[0100]

[0101] in, For residual Doppler frequency shift, This is the accumulated value of the phase difference between the subsequences. This is the time interval between segments.

[0102] Through the above steps, the residual Doppler frequency shift can be estimated by utilizing the phase change between adjacent preamble code sequences and the inter-segment time interval, thereby obtaining more accurate frequency offset information. This provides a basis for frequency offset correction for subsequent phase compensation of sub-correlation values, improving coherent merging effect, and enhancing the accuracy of timing advance determination.

[0103] S13063. Perform phase compensation on the sub-correlation values ​​at multiple time offset candidate positions based on the residual Doppler frequency shift to obtain the compensation value at each of the time offset candidate positions.

[0104] Among them, the time offset candidate position can be multiple discrete sampling positions used for timing search, the subcorrelation value can be the complex result obtained by correlation calculation between each preamble subsequence and the local reference subsequence at the corresponding time offset candidate position, and the compensation value can be the correlation result obtained after residual frequency offset phase correction of the subcorrelation value.

[0105] In one embodiment, the compensation value at each candidate time offset position can be calculated as follows: for any candidate time offset position, obtain the phase reference time corresponding to each preamble code sequence, generate the phase compensation factor corresponding to each preamble code sequence based on the residual Doppler frequency shift and the phase reference time; use the phase compensation factor to perform complex rotation correction on the sub-correlation value to obtain the compensation value, and the specific calculation formula is as follows:

[0106] in, For residual Doppler frequency shift, For the first Phase reference time of each subsequence For the first Subsequences at candidate time offset positions Sub-correlation values, For the first Subsequences at candidate time offset positions The compensation value below.

[0107] Through the above steps, the residual Doppler frequency shift can be used to perform phase correction on the sub-correlation values ​​at different time offset candidate positions, thereby reducing the correlation phase rotation and coherent accumulation loss caused by the residual frequency shift. This allows the correlation results of multiple preamble sub-sequences to be subsequently merged under a unified phase reference, thereby improving the concentration of correlation peaks and the accuracy of timing advance determination.

[0108] S13064. Determine the timing peak position based on the compensation value at each of the time offset candidate positions, and determine the timing advance based on the timing peak position.

[0109] Among them, the compensation value at each time offset candidate position can be the complex correlation result after residual Doppler frequency shift phase correction, the timing peak position can be the time offset candidate position with the largest correlation strength after the compensation value is merged, and the timing advance can be the time adjustment amount determined according to the offset of the timing peak position relative to the preset timing reference position, which is used to indicate the length of time that the uplink transmission time of the terminal device needs to be advanced.

[0110] In one embodiment, the timing peak position can be determined by: for any candidate time offset position, coherently merging the compensation values ​​corresponding to multiple preamble code sequences at the candidate time offset position to obtain the merged correlation value corresponding to the candidate time offset position; calculating the magnitude of the merged correlation value, and determining the candidate time offset position with the largest magnitude of the merged correlation value as the timing peak position.

[0111] In one embodiment, determining the timing advance based on the timing peak position can be achieved by: obtaining the sampling sequence number corresponding to the timing peak position and the reference sampling sequence number corresponding to the preset timing reference position; determining the difference between the sampling sequence number and the reference sampling sequence number as the sampling offset; and then multiplying the sampling offset by the preset sampling period to obtain the timing advance. The specific calculation formula is shown below:

[0112] in, To allow for advance timing, This is the sampling sequence number corresponding to the timing peak position. The reference sampling number, This is the preset sampling period.

[0113] Through the above steps, a stable timing peak position can be determined based on the correlation results after residual Doppler compensation, and the peak position can be converted into the timing advance corresponding to the terminal, thereby improving the accuracy and reliability of timing advance determination and providing a basis for subsequent uplink transmission timing adjustment, receive window configuration and terminal synchronization control.

[0114] Optionally, determining the timing peak position based on the compensation value at each of the candidate time offset positions includes: At each of the aforementioned time offset candidate positions, the compensation values ​​belonging to the same time offset candidate position are coherently merged to obtain the merged result of each of the aforementioned time offset candidate positions.

[0115] The merged result can be used to characterize the overall correlation matching strength corresponding to the current time offset candidate position.

[0116] In one embodiment, the method for coherently merging compensation values ​​belonging to the same time offset candidate position can be as follows: for any time offset candidate position, obtain the compensation value corresponding to each preamble code sequence under that time offset candidate position, and perform complex summation of multiple compensation values ​​according to the order of the preamble code sequences to obtain the merging result corresponding to that time offset candidate position.

[0117] Through the above steps, the compensation values ​​corresponding to multiple preamble code sequences at each candidate time offset position can be phase-consistently merged into complex numbers, which enhances the effective correlation components in the merging result and suppresses the influence of random noise and local interference on timing decisions, providing a reliable basis for subsequently determining the timing peak position and timing advance based on the merging result.

[0118] The merging result is moduloed to obtain the merging magnitude corresponding to each of the candidate time offset positions.

[0119] In one embodiment, the modulo operation of the merged result can be as follows: for any candidate time offset position, obtain the merged result corresponding to the candidate time offset position, add the square of the real part and the square of the imaginary part of the merged result, and perform a square root operation on the added result to obtain the merged magnitude corresponding to the candidate time offset position.

[0120] Through the above steps, the complex form of the merged result can be converted into a directly comparable amplitude metric, eliminating the influence of phase angle differences on peak determination, and enabling the correlation intensity of each time offset candidate position to be compared on a unified scale, providing a basis for subsequent determination of timing peak position and calculation of timing advance.

[0121] The candidate position with the largest merging amplitude is selected as the timing peak position.

[0122] Among them, the timing peak position can be used to characterize the optimal timing position of the terminal preamble in the receiver detection window.

[0123] In one embodiment, the method for selecting the timing peak position may be: obtaining the merging amplitude corresponding to each time offset candidate position, comparing multiple merging amplitudes according to their numerical values, determining the merging amplitude with the largest value, and determining the time offset candidate position corresponding to the largest merging amplitude as the timing peak position.

[0124] Through the above steps, the timing position with the highest correlation strength can be determined from multiple time offset candidate positions, so that the preamble detection results are concentrated at the most likely arrival time, providing an accurate basis for subsequent calculation of timing advance based on timing peak position, configuration of uplink receiving window and execution of terminal equipment synchronization adjustment.

[0125] Optionally, Figure 6 This is a flowchart illustrating the steps of a segmented random access preamble processing method provided in an embodiment of this application. (Reference) Figure 6 The segmented random access preamble processing method specifically includes: S201, Estimate Doppler frequency offset.

[0126] In one embodiment, the terminal device receives a downlink reference signal transmitted by the base station and estimates the Doppler frequency offset corresponding to the current link based on the downlink reference signal. The terminal device determines the downlink Doppler frequency offset by using the frequency offset relationship between the local reference sequence and the received signal, providing a basis for frequency offset estimation for subsequent uplink pre-compensation.

[0127] S202. Calculate the uplink pre-compensation amount based on the Doppler frequency offset.

[0128] In one embodiment, the terminal device calculates the uplink pre-compensation amount based on the estimated Doppler frequency offset. Specifically, the terminal device can map the downlink Doppler frequency offset to an uplink Doppler frequency offset prediction value based on the proportional relationship between the downlink Doppler frequency offset and the uplink and downlink carrier frequencies, and then take the inverse of the uplink Doppler frequency offset prediction value to obtain the uplink pre-compensation amount. The uplink pre-compensation amount is used to perform reverse frequency compensation on the preamble baseband signal before the terminal device transmits the preamble, so as to reduce the residual Doppler frequency offset when the preamble arrives at the base station.

[0129] For example, the uplink pre-compensation amount can be expressed as:

[0130] in, Indicates the uplink pre-compensation amount. Indicates downlink Doppler frequency offset. Indicates the uplink carrier frequency. This indicates the downlink carrier frequency.

[0131] S203. Generate a segmented second preamble baseband signal, and perform phase rotation on the second preamble baseband signal according to the uplink pre-compensation amount to generate a third preamble baseband signal.

[0132] In one embodiment, the terminal device generates a segmented preamble baseband signal as the second preamble baseband signal. The second preamble baseband signal includes multiple preamble sub-sequences, and inter-segment guard intervals can be set between adjacent preamble sub-sequences to reduce temporal interference between them. The terminal device generates a phase rotation factor based on the uplink pre-compensation amount and multiplies the second preamble baseband signal by the phase rotation factor to obtain the third preamble baseband signal. This phase rotation processing is used to apply frequency pre-compensation to the baseband signal before transmission, so that the Doppler frequency offset generated by the uplink preamble during propagation is canceled in advance.

[0133] S204, Uplink transmission of the third preamble baseband signal.

[0134] In one embodiment, the terminal device modulates the third preamble baseband signal onto the uplink carrier and transmits it to the base station via the uplink. Since the third preamble baseband signal has undergone uplink pre-compensation processing, even if there is a Doppler frequency shift caused by high-speed relative motion during signal propagation, the preamble signal obtained by the receiver can still maintain a low residual frequency offset.

[0135] S205, the satellite receives the third preamble baseband signal.

[0136] In one embodiment, the satellite base station receives the third preamble baseband signal sent by the terminal equipment and performs down-conversion, sampling, and baseband processing on the received signal to obtain the received baseband signal for preamble detection. Since the terminal equipment has already performed uplink pre-compensation, the frequency offset in the preamble signal detected by the receiver is weakened, but residual frequency offset may still exist. Therefore, further segmented correlation detection and phase compensation are required.

[0137] S206. Segment the baseband signal of the third preamble and calculate the sub-correlation value of each sub-sequence.

[0138] In one embodiment, the receiver segments the third preamble baseband signal according to the segmented structure of the preamble, obtaining multiple signal segments to be detected corresponding to preamble sub-sequences. For each signal segment to be detected, the receiver performs correlation operations with the corresponding preamble sub-sequence stored locally to obtain the sub-correlation result of each sub-sequence, and extracts the sub-correlation peak value, i.e., the sub-correlation value, from the sub-correlation result.

[0139] S207. Calculate the phase difference of the subsequence.

[0140] In one embodiment, the receiving end calculates the subsequence phase difference based on the subcorrelation peaks of adjacent subsequences. Specifically, the conjugate of the subcorrelation peak of the preceding subsequence can be multiplied by the subcorrelation peak of the following subsequence to obtain the complex phase relationship between adjacent subsequences. Then, the phase angle of this complex phase relationship is extracted to obtain the subsequence phase difference between adjacent subsequences.

[0141] S208. The sub-correlation values ​​of the sub-sequences are compensated and merged using the phase difference of the sub-sequences to obtain the timing advance.

[0142] In one embodiment, the receiver determines a phase compensation factor based on the sub-sequence phase difference and uses this factor to perform phase correction on the sub-correlation values ​​of the sub-sequences, adjusting the sub-correlation values ​​of multiple sub-sequences to a unified phase reference. Subsequently, the compensated sub-correlation values ​​are coherently combined to obtain a combined correlation result. Since coherent combining can enhance the correlation peak corresponding to the true preamble position and suppress phase inconsistencies caused by noise and residual frequency offset, the receiver can determine the preamble arrival time position based on the combined correlation result. The base station calculates the timing advance corresponding to the terminal equipment based on the offset between the preamble arrival time position and the preset timing reference position.

[0143] Based on the above embodiments, Figure 7 This is a structural block diagram of a segmented random access preamble processing device provided in an embodiment of this application. (Reference) Figure 7 The segmented random access preamble processing device provided in this embodiment specifically includes: a signal acquisition module 11, a signal segmentation module 12, and a compensation transmission module 13.

[0144] The signal acquisition module 11 is configured to acquire a first preamble baseband signal representing a random access preamble sequence; the signal segmentation module 12 is configured to segment the first preamble baseband signal to obtain a second preamble baseband signal, the second preamble baseband signal including multiple preamble sub-sequences, with an inter-segment guard interval between adjacent preamble sub-sequences; and the compensation transmission module 13 is configured to perform Doppler compensation on the second preamble baseband signal to obtain a third preamble baseband signal, and transmit the third preamble baseband signal to the base station for the base station to determine a timing advance based on the third preamble baseband signal.

[0145] Based on the above embodiments, the compensation transmission module 13 includes: a Doppler unit configured to acquire a synchronization information block signal and determine the Doppler frequency offset and Doppler change rate based on the synchronization information block signal; a rotation factor unit configured to calculate an uplink pre-compensation amount based on the Doppler frequency offset and the Doppler change rate, and generate a rotation factor based on the uplink pre-compensation amount; and a signal compensation unit configured to compensate the second preamble baseband signal based on the rotation factor to obtain a third preamble baseband signal.

[0146] Based on the above embodiments, the compensation transmission module 13 further includes: a signal extraction unit configured to extract multiple preamble sub-sequences from the third preamble baseband signal; a phase difference unit configured to calculate the sub-sequence phase difference between adjacent preamble sub-sequences; and a compensation merging unit configured to compensate and merge the sub-correlation values ​​of the multiple preamble sub-sequences according to the sub-sequence phase difference to obtain a timing advance.

[0147] Based on the above embodiments, the phase difference unit includes: a candidate position subunit, configured to determine multiple time offset candidate positions according to a preset time offset search window and a preset sampling period; a sub-correlation value subunit, configured to perform correlation calculations on each of the preamble sub-sequences at the multiple time offset candidate positions to obtain the sub-correlation value corresponding to each preamble sub-sequence at each of the time offset candidate positions; a conjugate product subunit, configured to calculate the conjugate product of the sub-correlation values ​​of adjacent preamble sub-sequences at the same time offset candidate position; and a sequence phase difference subunit, configured to determine the sub-sequence phase difference corresponding to the time offset candidate position based on the conjugate product.

[0148] Based on the above embodiments, the sequence phase difference subunit includes: an initial phase difference component configured to calculate the phase angle of the conjugate product to obtain the initial phase difference of adjacent preamble subsequences; a phase unwrapping component configured to unwrap the initial phase difference to obtain the unwrapped phase difference of adjacent preamble subsequences; and a phase averaging component configured to calculate the average value of the unwrapped phase difference to obtain the subsequence phase difference corresponding to the time offset candidate position.

[0149] Based on the above embodiments, the compensation merging unit includes: an inter-segment interval subunit, configured to acquire the subsequence duration of the preamble subsequence and the guard interval duration of the inter-segment guard interval, and add the subsequence duration and the guard interval duration to obtain the inter-segment time interval; a Doppler frequency shift subunit, configured to calculate the residual Doppler frequency shift based on the inter-segment time interval and the subsequence phase difference; a compensation value subunit, configured to perform phase compensation on the sub-correlation values ​​at multiple time offset candidate positions based on the residual Doppler frequency shift, to obtain the compensation value at each of the time offset candidate positions; and a timing advance quantum unit, configured to determine the timing peak position based on the compensation value at each of the time offset candidate positions, and determine the timing advance amount based on the timing peak position.

[0150] Based on the above embodiments, the timing advance quantum unit includes: a coherent merging component configured to coherently merge compensation values ​​belonging to the same time offset candidate position at each of the time offset candidate positions to obtain a merging result for each of the time offset candidate positions; a merging amplitude component configured to take the modulus of the merging result to obtain a merging amplitude corresponding to each of the time offset candidate positions; and a peak position component configured to select the time offset candidate position with the largest merging amplitude as the timing peak position.

[0151] The segmented random access preamble processing device provided in this application embodiment, through the coordinated processing of the signal acquisition module 11, the signal segmentation module 12, and the compensation transmission module 13, realizes the acquisition, segmentation, Doppler compensation, and uplink transmission of the random access preamble baseband signal, thereby improving the transmission reliability of the preamble in scenarios with large frequency offset. Specifically, the signal acquisition module 11 acquires the first preamble baseband signal representing the random access preamble sequence, providing the original signal basis for subsequent segmentation and compensation processing. The signal segmentation module 12 segments the first preamble baseband signal to obtain a second preamble baseband signal. The second preamble baseband signal includes multiple preamble sub-sequences, with inter-segment guard intervals between adjacent preamble sub-sequences to reduce temporal interference between sub-sequences and facilitate segmentation detection at the receiver. The compensation transmission module 13 performs Doppler compensation on the second preamble baseband signal to obtain a third preamble baseband signal and transmits the third preamble baseband signal to the base station. Doppler compensation can offset the frequency offset during uplink transmission in advance, improving the accuracy of preamble detection and timing estimation at the base station.

[0152] The segmented random access preamble processing device provided in this application embodiment can be used to execute the segmented random access preamble processing method provided in the above embodiment, and has corresponding functions and beneficial effects.

[0153] Figure 8 This is a schematic diagram of the structure of a segmented random access preamble processing device provided in an embodiment of this application, with reference to... Figure 8 The segmented random access preamble processing device includes a processor 21, a memory 22, a communication device 23, an input device 24, and an output device 25. The number of processors 21 and the number of memories 22 in the segmented random access preamble processing device can be one or more. The processor 21, memory 22, communication device 23, input device 24, and output device 25 of the segmented random access preamble processing device can be connected via a bus or other means.

[0154] The memory 22, as a computer-readable storage medium, can be used to store software programs, computer-executable programs, and modules, such as program instructions / modules corresponding to the segmented random access preamble processing method in any embodiment of this application (e.g., signal acquisition module 11, signal segmentation module 12, and compensation transmission module 13 in the segmented random access preamble processing device). The memory 22 may primarily include a program storage area and a data storage area. The program storage area may store the operating system and at least one application program required for a function; the data storage area may store data created based on the use of the device, etc. Furthermore, the memory 22 may include high-speed random access memory and may also include non-volatile memory, such as at least one disk storage device, flash memory device, or other non-volatile solid-state storage device. In some instances, the memory may further include memory remotely located relative to the processor, and these remote memories can be connected to the device via a network. Examples of such networks include, but are not limited to, the Internet, corporate intranets, local area networks, mobile communication networks, and combinations thereof.

[0155] The communication device 23 is used for data transmission.

[0156] The processor 21 executes various functional applications and data processing of the device by running software programs, instructions and modules stored in the memory 22, thereby realizing the segmented random access preamble processing method described above.

[0157] Input device 24 can be used to receive input digital or character information, and to generate key signal inputs related to user settings and function control of the device. Output device 25 may include display devices such as a display screen.

[0158] The segmented random access preamble processing device provided above can be used to execute the segmented random access preamble processing method provided in the above embodiments, and has corresponding functions and beneficial effects.

[0159] This application embodiment also provides a storage medium containing computer-executable instructions. When executed by a computer processor, the computer-executable instructions are used to perform a segmented random access preamble processing method. The segmented random access preamble processing method includes: acquiring a first preamble baseband signal representing a random access preamble sequence; segmenting the first preamble baseband signal to obtain a second preamble baseband signal, the second preamble baseband signal including multiple preamble sub-sequences, with an inter-segment guard interval set between adjacent preamble sub-sequences; performing Doppler compensation on the second preamble baseband signal to obtain a third preamble baseband signal; and sending the third preamble baseband signal to a base station, for the base station to determine a timing advance based on the third preamble baseband signal.

[0160] Storage medium—any type of memory device or storage device. The term "storage medium" is intended to include: mounting media, such as CD-ROM, floppy disk, or magnetic tape devices; computer system memory or random access memory, such as DRAM, DDR RAM, SRAM, EDO RAM, etc.; non-volatile memory, such as flash memory, magnetic media (e.g., hard disk or optical storage); registers or other similar types of memory elements, etc. Storage medium may also include other types of memory or combinations thereof. Furthermore, storage medium may reside in a first computer system in which a program is executed, or it may reside in a different second computer system connected to the first computer system via a network (such as the Internet). The second computer system can provide program instructions to the first computer for execution. The term "storage medium" may include two or more storage media residing in different locations (e.g., in different computer systems connected via a network). Storage medium may store program instructions (e.g., specifically implemented as a computer program) executable by one or more processors.

[0161] Of course, the computer-executable instructions provided in the embodiments of this application are not limited to the segmented random access preamble processing method described above, but can also execute related operations in the segmented random access preamble processing method provided in any embodiment of this application.

[0162] The segmented random access preamble processing device, storage medium, and segmented random access preamble processing equipment provided in the above embodiments can execute the segmented random access preamble processing method provided in any embodiment of this application. For technical details not described in detail in the above embodiments, please refer to the segmented random access preamble processing method provided in any embodiment of this application.

[0163] The above description is merely a preferred embodiment and the technical principles employed in this application. This application is not limited to the specific embodiments described herein, and various obvious changes, readjustments, and substitutions that can be made by those skilled in the art will not depart from the scope of protection of this application. Therefore, although this application has been described in detail through the above embodiments, this application is not limited to the above embodiments, and may include many other equivalent embodiments without departing from the concept of this application. The scope of this application is determined by the scope of the claims.

Claims

1. A segmented random access preamble processing method, applied to a terminal device, characterized in that, include: Acquire the first preamble baseband signal used to represent the random access preamble sequence; The first preamble baseband signal is segmented to obtain a second preamble baseband signal. The second preamble baseband signal includes multiple preamble sub-sequences, and an inter-segment guard interval is set between adjacent preamble sub-sequences. Doppler compensation is performed on the second preamble baseband signal to obtain a third preamble baseband signal, which is then sent to the base station for the base station to determine timing advance based on the third preamble baseband signal.

2. The segmented random access preamble processing method according to claim 1, characterized in that, The step of performing Doppler compensation on the second preamble baseband signal to obtain the third preamble baseband signal includes: Acquire the synchronization information block signal, and determine the Doppler frequency offset and Doppler rate of change based on the synchronization information block signal; The uplink pre-compensation amount is calculated based on the Doppler frequency offset and the Doppler rate of change, and the rotation factor is generated based on the uplink pre-compensation amount. The second preamble baseband signal is compensated based on the rotation factor to obtain the third preamble baseband signal.

3. The segmented random access preamble processing method according to claim 1, characterized in that, The determination of timing advance based on the third preamble baseband signal includes: Multiple preamble sequences are extracted from the third preamble baseband signal; Calculate the subsequence phase difference between adjacent preamble subsequences; The sub-correlation values ​​of multiple preamble sub-sequences are compensated and merged based on the phase difference of the sub-sequences to obtain the timing advance.

4. The segmented random access preamble processing method according to claim 3, characterized in that, The calculation of the subsequence phase difference between adjacent preamble subsequences includes: Multiple time offset candidate positions are determined based on a preset time offset search window and a preset sampling period; At multiple time offset candidate positions, correlation calculations are performed on each of the preamble sub-sequences to obtain the sub-correlation values ​​corresponding to each preamble sub-sequence at each of the multiple time offset candidate positions. At the same time offset candidate position, calculate the conjugate product of the subcorrelation values ​​of adjacent preamble code sequences; The phase difference of the subsequence corresponding to the candidate time offset position is determined based on the conjugate product.

5. The segmented random access preamble processing method according to claim 4, characterized in that, The step of determining the subsequence phase difference corresponding to the candidate time offset position based on the conjugate product includes: Calculate the phase angle of the conjugate product to obtain the initial phase difference between adjacent preamble codeword sequences; Phase unwrapping is performed on the initial phase difference to obtain the unwrapped phase difference of adjacent preamble codeword sequences; The average value of the unwrapped phase difference is calculated to obtain the subsequence phase difference corresponding to the candidate time offset position.

6. The segmented random access preamble processing method according to claim 3, characterized in that, The step of compensating and merging the sub-correlation values ​​of multiple preamble sub-sequences based on the sub-sequence phase difference to obtain a timing advance includes: Obtain the subsequence duration of the preamble subsequence and the protection interval duration of the inter-segment protection interval, and add the subsequence duration and the protection interval duration to obtain the inter-segment time interval; The residual Doppler frequency shift is calculated based on the inter-segment time interval and the sub-sequence phase difference; Phase compensation is performed on the sub-correlation values ​​at multiple time offset candidate positions based on the residual Doppler frequency shift to obtain the compensation value at each of the time offset candidate positions; The timing peak position is determined based on the compensation value at each of the candidate time offset positions, and the timing advance is determined based on the timing peak position.

7. The segmented random access preamble processing method according to claim 6, characterized in that, The step of determining the timing peak position based on the compensation value at each of the candidate time offset positions includes: At each of the aforementioned time offset candidate positions, the compensation values ​​belonging to the same time offset candidate position are coherently merged to obtain the merging result of each of the aforementioned time offset candidate positions; The merging result is moduloed to obtain the merging magnitude corresponding to each of the candidate time offset positions; The candidate position with the largest merging amplitude is selected as the timing peak position.

8. A segmented random access preamble processing device, applied to terminal equipment, characterized in that, include: The signal acquisition module is configured to acquire a first preamble baseband signal representing a random access preamble sequence; The signal segmentation module is configured to segment the first preamble baseband signal to obtain a second preamble baseband signal. The second preamble baseband signal includes multiple preamble sub-sequences, and an inter-segment guard interval is provided between adjacent preamble sub-sequences. The compensation transmission module is configured to perform Doppler compensation on the second preamble baseband signal to obtain a third preamble baseband signal, and transmit the third preamble baseband signal to the base station for the base station to determine the timing advance based on the third preamble baseband signal.

9. A segmented random access preamble processing device, characterized in that, include: One or more processors; A memory that stores one or more programs, which, when executed by one or more processors, enable the one or more processors to implement the segmented random access preamble processing method as described in any one of claims 1-7.

10. A storage medium containing computer-executable instructions, characterized in that, The computer-executable instructions, when executed by a computer processor, are used to perform the segmented random access preamble processing method as described in any one of claims 1-7.

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